They can be used to join together two clauses in a sentence. However, the clauses need to make sense on their own. For example: I had a terrible cold. I still went to work. You can add the ...

Editor's Note: APYs listed in this article are up-to-date as of the time of publication. They may fluctuate (up or down) as the Fed rate changes. CNBC Select will update as changes are made public.